Field of the Disclosure
The present application relates to a flexible display device.
Description of the Related Art
Nowadays, portable terminals such as a wireless terminal, a personal digital assistant (PDA), a portable multimedia player (PMP), an electronic notebook and so on are being trendily made small-sized for portability. Such portable terminals supply users with a variety of information such as character information, motion images, still images, MP3, game and so on through their screens. As such, the portable terminals each require a display unit to enlarge or widen the screen.
Meanwhile, miniaturization of the portable terminals forces the screen of the display unit to be small-sized. Due to this, it is difficult to satisfy both of the two requirements.
To address this matter, a portable terminal adopting a flexible display unit is being recently introduced. For example, a cylindered portable terminal can be introduced. The cylindered portable terminal rolls the flexible display unit and preserves the flexible display device in a rolled state when an active matrix screen is not used. The flexible display unit includes a display panel which uses a thin plastic substrate instead of a glass substrate.
However, the flexible display unit ejected from a body must have lower flatness than that of a rigid display unit using a glass substrate because of its high flexibility. Also, as the flexible display unit is preserved within the body in the rolled state, the flexible display unit ejected from the body must be re-rolled or curved due to restoring force which enables the flexible display unit to return to the rolled state.